The long range purpose of this project is to study the mechanism of toxicity and carcinogenicity of N-acetylarylamines and related compounds. The topics of present interest are: 1) The relationship between the induction of aryl hydrocarbon hydroxylase and N-hydroxylation of N-acetylarylamines after administration of polycyclic aromatic hydrocarbons to the inbred strains of mice C57BL/6N and DBA/2N and their progeny as well as other species. 2) The role of glutathione in protecting the developing fetus and the adult animals from the harmful effects of electrophilic metabolites arising from N-acetylarylamines. 3) The mechanism of species differences in N-hydroxylation of N-acetylarylamines in liver microsomes. 4) The relationship between mutagenicity and carcinogenicity of N-acetylarylamines. 5) The effect of partial hepatectomy on metabolism and carcinogenicity of N-acetylarylamines in mice. 6) The role of vitamin A in modifying the covalent binding of N-acetylarylamines to hepatic DNA. 7) The characterization of monooxygenase(s) system in ovaries from rats and mice and its potential role in chemically induced ovarian cancer.